\( \displaystyle A = - 1,6:\left( {1 + {2 \over 3}} \right) = {{ - 16} \over {10}}:{5 \over 3}\)\( \displaystyle = {{ - 8} \over 5}.{3 \over 5} = {{ - 24} \over {25}}\)
\( \displaystyle B = 1,4.{{15} \over {49}} - \left( {{4 \over 5} + {2 \over 3}} \right):2{1 \over 5} \)
\( \displaystyle = {{14} \over {10}}.{{15} \over {49}} - \left( {{{12 + 10} \over {15}}} \right):{{11} \over 5}\)
\( \displaystyle = {3 \over 7} - {{22} \over {15}}.{5 \over {11}} = {3 \over 7} - {2 \over 3} \)\(\displaystyle = {{9 - 14} \over {21}} = {{ - 5} \over {21}}\)